You mean that guy who was in France complaining that IB didn't let him free-ride past his margin? LOL! Explains a lot then.
If you have witnessed it several times, it is not rare, as rare events are scarcely witnessed. Good money managers don't run out of money. Bad money managers and bad traders do. And after they blow thier own stakes, they blow the stakes of others, first thier freinds and family, and then perfect strangers. Pro, if his appeal is not an outright con, is likely entering the latter part of the second phase of the blowout process. He can't get any money from anyone who knows him so he is appealing to strangers. It is revealing that you are sympathetic to the amateurish Pro.
Try this. Sometimes good traders loose their capital because of a situation with the backer unrelated to trading. Also, sometimes good traders have to use their trading capital for some event unrelated to trading.